Heated wiper for lasting machine



Dec. 13, 1960 J. s. KAMBORIAN HEATED WIPER FOR LASTING MACHINE Filed May 2, 1958 y a? 2? if United States Patent Hire Patented Dec. 13, i fifi HEATED WIPER non LASTING MACHINE Jacob S. Kamhorian, West Newton, Mass. International) Shoe Machine Co., 292 Main St., Cambridge, Mass.

Filed May 2, 1958, Ser. No. 732,721

'1 Claim. (Cl. 128.3)

This invention relates to shoe lasting apparatus of the kind in which a pair of oppositely turning rolls grip the lasting margin, stress it heightwise and then release it to a rotary wiper which operates on the stressed margin to fold it inwardly and downwardly onto the insole and wherein hot thermoplastic adhesive is supplied to the angle between the insole and the lasting margin just before the latter is laid down for attaching the margin to the insole.

The wiper operates to press the margin hard against the insole and to stress it inwardly away from the shoulder of the last; hence, even though care is taken to control the amount of adhesive delivered to the angle between the margin of the insole and the margin of the upper some of the adhesive squeezes out onto the insole beyond the lasting margin. A part of this excess adhesive is picked up by the wiper and although the wiper may be heated by conduction from its bearing or by playing a flame on its surface it cannot be maintained at a temperature uniform enough and high enough by such means as to be entirely effective in keeping the adhesive on its surface liquid hence some of the adhesive congeals thereon thus impairing its operation and some of it is smeared on the surface of the lasting margin. The adhesive smeared on the lasting margin is particularly objectionable because it gums up the buffing wheel during the subsequent roughing operation preparatory to the bottom attaching operation. Such of the adhesive as is squeezed out, which is not picked up by the wiper, because of its quick-setting characteristics hardens in a ridge or lumps on the insole and has to be removed. The use of a gas flame is furthermore objectionable because it is impossible to maintain a uniform temperature and because the nozzle must be set close to the wiper and in an upright position and consequently soon becomes clogged up with adhesive and will not function. The naked flame is also a fire hazard. Electrical heating of the wiper from its bearing, by way of conduction, is impractical for the high temperature required cannot be obtained without overheating the bearing and other parts of the apparatus.

The principal object of this invention is to provide means for heating the wiper to a temperature hot enough to keep any excess adhesive which is squeezed out be neath the lasting margin, liquid, so that instead of accumulating on the wiper and being transferred thereby to the outer surface of the lasting margin it will be spread out in a thin, uniform, unobjectionable layer on the insole. Other objects are to provide a way of heating the wiper to a high temprature Without danger of overheating the wiper bearing or adjacent parts of the machine, or burning the operator and/or producing fire hazard, of controlling the temperature to which the Wiper may be heated and of maintaining it uniform.

As herein illustrated, there is bearing means mounting a hollow elongate element of circular cross-section for rotation about its longitudinal axis, which has a portion projecting forwardly from the bearing for operating on the margin of the lasting margin in a direction to lay it down on the insole and a portion extending rearwardly from the bearing adapted to be connected to a driving member. A heating element is disposed in the forwardly extending portion and there is means on the rearwardly extending portion connected to a source of electric power for supplying current to the heating element. The latter means comprises a pair of axially spaced slip rings mounted externally of the rearwardly projecting portion which are insulated from each other and from the wiper element, which are connected respectively to the heating element by conductors extending rearwardly therefrom through the wiper to the rings. A pair of brushes are supported in engagement with the external surfaces of the rings and these are connected to a source of electric power by a suitable circuit containing means for regulating the amount of current supplied through the brushes to the heating unit and other means for maintaining the temperature of the heating unit substantially constant.

The invention will now be descriibed in greater detail with reference to the accompanying drawing wherein:

Fig. l is a horizontal section of the mounting longitudinally of the wiper, showing the wiper partly in section, taken on the line 1-1 of Fig. 2;

Fig. 2 is an elevation as seen from the lower side of Fig. 1;

[Fig 3 is a section taken on the line 33 of Fig. 1;

Fig. 4 is a fragmentary enlarged diametrical section showing the conductors extending from the heating element to the slip rings;

Fig. 5 is a plan view of the bottom of a shoe showing the relation of the feed rolls and wiper and the margin partly laid down and further showing the excess adhesive spread inwardly of the lasting margin; and

Fig. 6 is a fragmentary vertical section taken on the line 66 of Fig. 5.

Referring to the drawing, there is shown a bearing mount 10 supporting a rigid elongate wiper element 12 of circular cross-section in a substantially horizontal position for operating on the bottom of a shoe held up to it. The mount 10 is provided with suitable means for attaching it to the lasting machine next to the feed rolls r1 and r2 (Fig. 5), shown in the form of a C-shaped bracket 14, slidably engageable with a gib 16, the latter being mounted on a pneumatically supported block for up and down movement as shown in the pending application of Thomas A. Weisz, Serial No. 653,620, filed April 18, 1957, now Patent No. 2,915,763 dated December 8, 1959. The wiper element 12 has an intermediate portion 18 (Fig. l), rotatably supported within a bearing opening 20 in the mount, a forwardly projecting portion 22 and a rearwardly projecting portion 24. The intermediate portion 18 is supported at its forward end in the bearing opening by elongate slender roller bearings 26 and at its rear end by a ball bearing assembly 28. The roller bearings 26 are held in place by a snap ring 25 engaged within a groove internally of the bearing opening. A washer 27 is also employed in conjunction with the snap ring to prevent lubricant in the bearing from leaking out and travelling forwardly along the wiper. The ball bearing assembly 28 is held in the bearing opening by a snap ring 31 engaged within a groove internally thereof, and axial movement of the wiper is prevented by engagement of a shoulder 32 on the portion 18, at one side of the ball bearing assembly and a nut 34 threaded on the portion 24 at the other side.

Between the roller bearings and the ball hearing assembly there is an annular space for lubricant and the latter is forced into the space through a lateral opening 21, into which may be screwed an Alemite fitting.

Normally the opening is closed by a threaded plug 23. The forward portion 22 of the wiper element has on its external surface a helical rib 36 and an axial opening 37 within which is situated a heating element 38. The helix of the rib may be or any desired pitch. Any suitable type of heating element maybe employed,

- preferably a cartridge-type heater, containing a thermoi stat, diagrammatically indicated in Fig. 4 at T, that may be slipped in through the forward end of the opening 37' against a hollow Teflon bumper 39, at the inner end of the opening. The Teflon bumper 39 serves as an insulator which retards heat transfer by conductance, rearwardly from the heating element toward the hearing. The opening 37 is threaded at its outer end and normally closed by means of a threaded plug 42;

The rearwardly projecting portion 24 of the wiper element has mounted on its external surface, axially spaced metal slip rings 4444, which are insulated from each other and from the element by a non-metallic sleeve 46' (Fig. 4), mounted on the rearwardly extending portion which has axially spaced grooves 48-48 for reception of the slip rings 4444.

The heating element 38 is electrically connected to the slip rings by a pair of conductors 5050, extending rearwardly therefrom through a small diameter passage through the intermediate portion 18 into the portion 24 and through radially disposed openings 52-52 through the portion 24 and the sleeve 46, into contact with the inner sides of the slip rings 4444. A pair of brushes 5454 are supported in engagement with the external surfaces of the slip rings by a block 56 supported in an opening 58 in the mount 10. The block may be adjusted to hold the brushes in contact with the slip rings by means of a set screw 60 (Fig. 2). Conductors 62 provide for connecting the brushes to a source of electric power AG, and to provide for regulating the heat a rheostat or sim ilar variable resistance device 64 may be employed (Fig. 4), to control the amount of current to the heating element.

The rear end of the portion 24 has fastened to it a flexible coupling element 65, which in turn is detachably connected to a drive shaft 66.

As thus designed the heat is supplied directly to the operating part of the wiper without exposing the bearings of the wiper to direct heat and the temperature may be kept constant and uniform without loss of heat and with an efficient use of the current. Thus, it is possible to adjust the temperature of the wiper for best performance for a given type of adhesive and for the upper materials being lasted. In any event the wiper is kept hot enough so that the adhesive is prevented from hardening on its surface and accumulating between the helices; consequently, any adhesive that squeezes out from beneath the lasting margin will not build up on the wiper but will spread in a thin uniform layer over the insole, inwardly of the margin, as shown in Figs. and 6. The adhesive will adhere to the insole rather than to the wiper because the insole is cooler and thus will be continuously removed from the wiper so that the wiper will be kept clean. As will be seen by reference to Fig. 6, the adhesive layer 0 on the insole, inwardly of the margin, is so thin that it is unobjectionable. Furthermore, by electrically heating the wiper the hazard of fire is eliminated, the psychological fear on the part of the operator of being burned is eliminated, and there is. never any need for stopping the machine to clean the wiper.

Heating of the wiper has the still further advantage that it shrinks the lasting; margin, producing a feather edge which results in. better defined edges and reduces the number and size of pleats thereby affording better end results in lasting. 7

It should be understood that the present disclosure is for the purpose of, illustration only and that this invention includes all modifications and equivalents which fall within the scope of the appended claim.

I claim: 7

A wiper assembly comprising a bearing mount having a bearing opening, a rigid'elongate, hollow wiper element disposed in the opening, said elongate element having an intermediate portion of somewhat smaller diameter than the opening, rotary bearing elements at opposite ends of the opening supporting the elongate element for rotation about its longitudinal axis, means holding the bearing elements in place against axial displacement, said mount having a lateral opening in it in communication. with the annular space between the bearing elements for receiving a lubricant, a portion of the elongate element extending forwardly from the bearing mount having on its external surface a helical rib for continuous operation on a margin which is to be stressed, a heating element disposed in the forward extension'with its rear end terminating substantially at the forward end of the bearing mount, a hollow, heat insulating bumper situated in the extension behind the rear end of the heating element, a threaded plug screwed into the forward end of the extension for removably holding the heating element therein clamped against the bumper, a rearward portion of the Wiper element carrying a flexible coupling element by means of which the wiper element is drivably connected to a drive shaft, slip rings mounted on said elongate element intermediate the flexible coupling element and the bearing mount, means insulating the slip rings from the elongate element and from each other, conductors extending through said hollow bumper connecting the heating element to the slip rings internally of the elongate element, a pair of brushes and means adjustably mounting the brushes in engagement with the slip rings externally of the elongate element. 1

References Cited in the file of this patent UNITED STATES PATENTS 1,559,637 Marsh Nov. 3, 1925 1,768,680 Goddu July 1, 1930 2,104,183 Brostrom Ian. 4, 1938 2,455,694 Miller Dec. 7, 1948 2,571,140 Kamborian Oct. 16, 1951 i l i 

